WASHINGTON – A judge on Friday took the Justice Department to task for failing to inform the Foreign Intelligence Surveillance Court that a federal court in California had issued orders to preserve phone data collected in a government surveillance program.

Reggie Walton, the chief judge of the surveillance court, said the Justice Department should have made him aware of the preservation orders. Walton is demanding a written explanation from government lawyers.

Walton says he expects the government to be far more attentive to its obligations in its practice before the court.

Last month, the department asked Walton to let the government keep phone data collected by the National Security Agency beyond a five-year limit, arguing that it has an obligation to retain evidence in lawsuits it is facing that challenge the surveillance.

Walton rejected the request, saying that groups suing the government over the NSA's phone data program had not asked that such information be preserved. In fact, a federal court in two cases in California had issued preservation orders.

Walton has since reversed his earlier decision so that the government can preserve phone data gathered beyond a five-year limit.

Walton said he reviewed some email traffic showing that as early as Feb. 26 — the day after the Justice Department request on phone data — groups challenging the NSA program were asking the department why it wasn't disclosing the preservation orders in the two California cases.

Walton granted a request by the challengers in the two cases to correct the record, an unusual step on the part of the surveillance court that by law, hears only from the government.

The judge also disclosed that there were preservation orders in two additional lawsuits — bringing the total to four.

Walton revealed that the information gathering at issue in two of the cases dealt with the "President's Surveillance Program" pursuant to executive authority, as opposed to the phone data collection program with oversight by the surveillance court.

Walton took note of the two different programs, suggesting that Justice Department attorneys may have perceived the preservation orders in the president's program to be immaterial to the issues in the lawsuits challenging the legitimacy of the NSA's phone collection program overseen by the FISC. Walton noted that lawyers for those filing the lawsuits disagreed with that explanation of why the Justice Department failed to notify the court.